Hello Hello. I wanted to ask if anyone have any advice in preventing from causing compression artifacts, macroblocking, square-ish blurs. It usually occurs in portions of videos where there is movement and/or there is a bit of detail on screen. Below is the video of what I mean. It is most noticeable at 0:30 and 0:40 minutes and it is present on all viewing resolution, including 1080p. Pretty much becomes a big blob. I uploaded that same video on another account and on another browser, and the issue occurs at the same place. These are not present in the rendered videos. I have about 90 different permutations of rendering settings for that same scene trying to get rid of it. I tried WMV, MP4 and using H.264. I tried using Sony Vegas, Adobe Premiere and some obscure editor called VSDC. I tried using fraps and different codecs with dxtory.. The raws are pretty as usual. For the above video. I got the best size/quality by editing and rendering my raw clip (about 4GB for 1:33 minute video) from FRAPs with Sony Vegas using the sony avc aac render setting with a constant bitrate of 50Mbps. It yielded me a 528MB file size that does not have any artifacts. Then I used avidemux and used x264 (10,000kbps) to compress the file size to 128MB mp4 file, and it looked not bad. I've had this issue for over half a year and have spent several "few days of 10+ hours each" trying to figure out how to make them go away or at least make them less noticeable. I do realize that youtube re-encodes your video and degrades quality, but it is not as obvious with other videos from other uploaders. Other people's video has very faint and/or smaller blocks. Not that it matters, but part of my comp specs are: i5 3570k (OC to 4.0ghrz) nvidia gtx 760 2GB vid card 8GB of ram "Up to 1mbps upload speed" for internet Generally, its not as crisp as other people's videos and the major issue is the darn square blurs. I can't tell if it is youtube's or is it my fault. Seeing how it likes to appear at the same spot, even after reupload. Is it because there is so much detail and movement going on at that point that the youtube encoder just shreds it? For WMV, the overall quality is not that great compare to MP4 (for the parts that doesnt have the damn square blurs in the MP4 vids), but not as much square blurs. This is how it would look if I use WMV I've been struggling with this for a while.